#!/bin/sh

if test $# -ne 1; then
    echo "Usage: `basename $0 .sh` <process-id>      " 1>&2
    exit 1
fi

if test ! -r /proc/$1; then
    echo "Process $1 not found." 1>&2
    exit 1
fi

backtrace="bt"
if test -d /proc/$1/task ; then
    # Newer kernel; has a task/ directory.
    if test `/bin/ls /proc/$1/task | /usr/bin/wc -l` -gt 1 2>/dev/null ; then
        backtrace="thread apply all bt"
    fi
elif test -f /proc/$1/maps ; then
    # Older kernel; go by it loading libpthread.
    if /bin/grep -e libpthread /proc/$1/maps > /dev/null 2>&1 ; then
        backtrace="thread apply all bt"
    fi
fi

GDB=${GDB:-gdb}

$GDB --quiet -nx $GDBARGS  /proc/$1/exe $1 <<EOF 2>&1 |
set width 0
set height 0
set pagination no
$backtrace
EOF

/bin/sed -n \
    -e 's/^\((gdb) \)*//' \
    -e '/^#/p' \
    -e '/^Thread/p'
